Theoretical study of the excited-state double proton transfer in the (3-methyl-7-azaindole)-(7-azaindole) heterodimer.

Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
Journal of Computational Chemistry (Impact Factor: 3.6). 05/2012; 33(20):1701-8. DOI: 10.1002/jcc.23000
Source: PubMed

ABSTRACT Excited-state double proton transfer (ESDPT) in the (3-methyl-7-azaindole)-(7-azaindole) heterodimer is theoretically investigated by the long-range corrected time-dependent density functional theory method and the complete-active-space second-order perturbation theory method. The calculated potential energy profiles exhibit a lower barrier for the concerted mechanism in the locally excited state than for the stepwise mechanism through the charge-transfer state. This result suggests that the ESDPT in the isolated heterodimer is likely to follow the former mechanism, as has been exhibited for the ESDPT in the homodimer of 7-azaindole.

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